Reply by richgreer

The rule of thumb I have heard is the lumber needs to air dry for 1 year plus another year for every inch of thickness (i.e. one inch thick lumber needs 2 years to dry, 2 inch thick needs 3 years, etc.).

Of course, there are variations based on heat, humidity and what kind of wood it is. Also, how the lumber was stored is a factor. The boards in the garage should have been separated by slates so air could circulate all around the boards. If not, the lumber will take much longer to dry.

I advise caution. No harm will come from the lumber drying longer than needed. Harm can come from working with it too early.